[quote=sam4books]
Ahh coolios :> Glad we can be on the same page and stuffs. Definitely gonna go down that "using blood as a weapon" route then!
[/quote]

Yeah, I'm a fan of that. I honestly hadn't thought of controlling it, but then I realized how OPed it can get. So yeah. Oh, and I forgot to mention, any blood that is no longer being controlled by someone else's "soul" is fair game. This brings the idea of the dead's blood and blood that has dropped from wounds. Also note that the blood is easier to control the older and more dead it gets. Also note that another restriction is the tax on the body due to bending. 

This goes for all benders, using one's bending is very physically taxing. Large amounts or intensities of bending will tire a person out. Imagine about 1.5 times what it would take to do whatever you are doing with your body. This helps even out benders and nonbenders. Physical training can help by making a person stronger and more enduranced (I made that word up), or by training one's bending. This helps reduce the amount of taxation caused by bending. Some say the best benders barely feel the body tax.